As Business Insider's car audiophile, I did most of the testing, but I debated my assessments with senior reporter Ben Zhang and deputy executive editor Cadie Thompson.

We don't have a scientific process, or even an elaborate methodology for this award. As was the case in 2017, however, we did review close to 70 vehicles in 2018, which exposed us to a wide variety of audio systems.

We tend to pick out what some setups do better than others, though most car audio these days is excellent. The old AM/FM, two-speaker arrangements of yesteryear are of course long gone.

The market is separated into three tiers: fairly basic systems; premium systems; and super-premium, high-end systems. These upmarket systems are often an option on luxury vehicles, and at times a pricey one. But in our view, they're well worth considering.

When listening to music in your car, you're likely to be surfing media: terrestrial radio, satellite radio, CDs, MP3s, Bluetooth streaming, and streaming audio services such as Pandora, Spotify, or Tidal.

You may also be using USB inputs or an aux jack, so the quality of your source audio will vary. This year again I found that the aux jack gave me the best modern audio, although some experts maintain that the USB port is better and that using a CD player, if available, still offers the finest sound.

The big winner

One of four roof speakers in the system. Matthew DeBord/BI

I sampled the Acura ELS Studio 3D system in the all-new 2019 Acura RDX, and I was monumentally impressed.

It comes in two versions. The 3D specification taps a 710-watt amplifier and includes four specialized overhead speakers to go along with 14 others throughout an Acura vehicle. The "base" system has 550 watts and 12 speakers.

According the Acura and ELS parent Panasonic — who jointly launched the system in early 2018 — the 3D configuration was tuned by "eight-time Grammy-winning producer and engineer Elliot Scheiner," who has worked with some of the biggest names in music, including the Eagles, Eric Clapton, Steely Dan, and the Foo Fighters.

In the two years we've been handing out the Audio System of the Year, I've highlighted the exquisite nature of Bowers & Wilkins, whose system won in 2016, and the admirable consistency of Bose, last year's victor.

What struck me about the ELS Studio 3D is, understandably, the professional aspect. Scheiner has been involved since 2004, and in an interview he told me that the goal with ELS was always to get "studio sound in the car." What that means is audio accuracy. That differs from, say, the sort raptures that Bowers & Wilkins and Burmester deliver. It also isn't the same as consistency across musical genres, which I've admired in Bose.

Instead, the ELS Studio 3D sounds incredibly real. It doesn't sound like you're listening to a raw studio mix. But it creates a rich analog impression for music coming from digital sources. It's the kind of audio system that musicians appreciate because it can max out a mix, showcasing the skills of the players and singers as well as the engineers. More than any other car-audio system, it proves music is a team sport.

In terms of the specifics, there isn't quite as much sparkle on highs as I've enjoyed with other premium systems, and the bass is less broad than what I'm used to from Bose and Harman Kardon. The midranges are expansive, and in the Acura RDX the soundstage truly was 3D, an envelope of music. My overall impression was that ELS Studio 3D is a real thinking person's system. Whether it was Zeppelin or the magical phrasings of Melody Gardot, the sound was serious and beautiful.

The runner-up

Tesla's minimalist interior is open and airy, the perfect stage for the in-house audio system. Hollis Johnson/Business Insider

Tesla designed its own audio system, and in both the Model X SUV and the new Model 3 sedan I've found it to be consistently impressive. It's a secret weapon for Tesla, and further proof the company wants to design and oversee as much of the vehicle experience as possible.

While it lacks the jaw-dropping capabilities of Burmester, the Harman-developed Revel Ultima setup found in Lincoln vehicles, and Bowers & Wilkins' deep audiophile credibility, Tesla audio makes compressed, streamed music sound wonderful. In my testing, the system has also been quite well tuned to the airy, open, minimalist interiors of Tesla's vehicles.

The remaining three systems are stunning. You aren't going to be disappointed in any way. Burmester, in particular, has shown me a steady talent for creating warm, concert-hall-like euphony, befitting the Mercedes-Benz automobiles in which I've encountered the system.